Denatured alcohol



LED SCHLECHT AND HANS BOE'IGER, OF LUDl/VIGS HLAFEN-GN-THE-RHINE, GERWIY, ASSIG-NORS TO I. 51-. EAR-BENINDUSTEIE AKTIENGESELLSCHAFT, OF FRANKEORT-QN- THE-MAIN, GER-DENY, A QOB-PSEATION 0F GEIRZVIANY 'J'EN'ATURED 1350059311 "r'l'o Brewing. Original application filed October 11, 1928, Serial No. 311,953, and. in Germany August 2,

1928. Divided and this application filed June 29, 1952.9.

The present application has been divided out from our copending application Ser. No. 311,953, filed @ctober 11, 1928.

F or the production of condensation products from acetylene and ammonia, it has also been proposed to employ apart from metal oxide, which can be reduced only with dll culty, catalytic substances consisting of incompletely reduced metallic compounds, In this. connection it 'essly stated that only such catalysts might be used in which no reduction. to

the metallic state occurs, whether prior to use or underthe reducing action of acetylene, since such reduction lowers the yield of condensation products.

No have now found that condensation products from acetylene and ammonia can be prepared in an advantageous manner by passing mixtures of the said gases or gases containing the same over catalytic substances containing such metals in the free state as do not assist the formation of carbon from acetylene to more than a slight extent, if at all. Such metals are the metals of the second subgroup of the first group to the sixth group of the periodic system and especially zinc, cadmium or gold, preferably in admixture with other substances, especially such metal compounds as are also catalytic, such as metal oxids. The metals of the iron group and also copper, and finely divided palladium or platinum cannot be employed, since they powerfully assist the decomposition of acetylene whereby losses and other disadvantages occur. Palladium and platinum can, however, be employed provided t iey exhibit a suitable character as regards surface, i. e., they are employed in a com,- pact state. Apart from a very long working life, the metalliferous catalytic substances possess the particular advantage over those already known, in that they furnish good yields at temperatures at which, for example, the known combinations of oxide have not begun to act. Thus with the described catalytic substances very good yields are obtained of heterocyclic compounds, principally coning of pyridine homologues at low ienioeratures as at 250 a do "erial 210. 374,941.

with a particularly high content of pyridine homologues is obtained by employing a cata-- lyst, the active component of which consists of one or more of the aforesaid metals singly.

A suitable method of preparing the catalytic substances comprising several active 1 substances consists in impregnating a highly having a reducing etlect as for example hydrogen. Catalyticsubstances of the described composition can also be obtained by impregnating suitable sparingly soluble components with readily soluble components, followed by a reducing treatment.

it is advisable to preheat the gaseous mixture prior to its admission into the contact chamber. The temperatures employed in the process range generally between 200 and 600 (3., but in many cases the best results are obtained at temperatures between 250 and @00 G. If desired, the process may be performed also at an elevated pressure as for example up to 3 atmospheres with acetylene and ammonia alone.

The resulting condensation products are particularly suitable for use as denaturing agents for alcohols (such as ethyl alcohol). The condensation products, which according to the temperature at which they are produced, consist chiefly of methylated pyridines (such as picoline, lutidine and collidine) in addition to more or less of acetonitrile and traces of pyridine, have a repellant smell and taste and dissolve readily in alcohol without turbidity occurring when such solution is diluted with water; Moreover it: is impossible to purity alcohol, denatured with these agents in any easily employed manner such as by filtration through active char- .oy distillation, or to mask the objectionable smell and taste completely by other strong-smelling or tasting substances.

In some cases, according to the purpose for which the denatured ,liquid is intended, it is advisable to employ only a certain fraction of the condensation product such as that passing over between 100 and 150 C. or to add other substances to the denaturing agent,

as for example, substances containing sulphur such as thiophene, mercaptan and the like, or mixtures thereof, such as can be obtained by acting upon acetylene or another unsaturated hydrocarbon with gaseous or 'Ewample 1 Active silica is impregnated with a solution of aluminium nitrate and cadmium nitrate, the mass being then dried, and treated with dry hydrogen at 100 C. for 12 hours. A mixture of acetylene and ammonia passed over this catalyst at 250 C. will furnish continually for days high yields of liquid condensation products, whereas, with aluminium oxid alone, under the same conditions and at the same temperature, no condensate is 'obtained.

Example 2 a A Zinc oxid is made into 'a suspension with, a dilute solution of gold chlorid, and dried in a reducing atmosphere, and a mixture of equal,

' volumes of acetylene and ammonia is passed dines, the main ver this catalyst at 450 C. The yield of liquid condensation pro-ducts is almost double the amount obtained with zinc oxid alone under otherwise equal conditions.

Silica gel is soaked with a s'olutionof cadmium nitrate and then exposed to a current of hydrogen at about 300 C. for several hours. A mixture of equal parts of ammonia 350 C over the catalyst prepared in the aforesaid manner whereby a condensate is obtained 80 per cent of which consists of pyriportion of which consists of picolines.

. Example 4 j A mixture of gases obtained by the elec- A trothermic decomposition of a natural gas.

in the presence of hydrogen and consisting of 7 parts by volume of hydrogen, 7 arts by volume of methane and 1 part by vo ume of acetyleneis mixed with 1 part by volume of ammonia and then passed over a catalyst prepared in accordance with Example 3. On cooling the reaction products a condensate is obtained which consists mainly of pyridines. The remaining gases can be subjected again to electrothermic decomposition and passed over the catalyst after adding ammonia. Also other gases containing acetylene such as those obtainable by the action of an electric are on coke oven gas, can be employed with similar good results. Example A pure 96 per cent solution of alcohol is denatured with 1 per cent of the crude condensate obtained by the catalytic condensation-of acetylene with ammonia at350 C. The denatured alcohol burns with a nonsmoky-fiame. On being diluted with Water down to an alcohol content of 40 per cent, no turbidity occurs. The bitter taste and char acteristic smell persists after the dilution and also after distillation and evenafter filtration through activech'arcoal. The denaturing effect can be increased by adding 2 per thousand of a fraction boiling below 150 0. of a product obtainable by passing a mixture of acetylene and hydrogen at 300 C. over granular pyrites and consisting mainly of thiophenes and similarheterocyclic sulphurbearing compounds and some mercaptans.

Weclaim: v 1. As a composition of matter denatured alcohol containing a small percentage of a synthetic mixture of acet0n1trile,"pyridine and its homologues and of a minute quantity of an organic, heterocyclic sulphur-bearing substance; 0 f I 2. As a composition of matter denatured ethyl alcohol 'comprisingabout'l per cent by volume of a synthetic mixture of acetoni trile, pyridine and itshomologues and about 2 per thousand of a heterocyclic sulphur bearing organic compound. t c 3. As a composition ofmatter, ethyl al-- cohol denatured with about 1 per cent by Volume of the crude condensate obtained by' the catalytic condensation of acetylene with ammonia at about 350? G. and containing acetonitrile, pyridine and its homologues, .and about 2 per thousand of a fraction boiling d bt bl b and acetylene *ispassed at from 300 C. to below 150 G of a Pm me 0 ama e y tures." s

. LEO SCHLECHT. HANS BOETGER. 

